ROLLING METHODS USING CORRUGATED ROLLS AND ROLLING SYSTEMS

Abstract

A rolling method using corrugated rolls and a rolling system are provided. The method includes billet preparation, first-pass rolling, second-pass rolling, and annealing. The billet preparation includes: stacking a cladding plate on a base plate to obtain a bimetallic laminated plate blank. The first-pass rolling includes: feeding the bimetallic laminated plate blank between two spaced-apart corrugated rolls for rolling to form a first bimetallic laminated plate. The second-pass rolling includes: feeding the first bimetallic laminated plate between two spaced-apart flat rolls for rolling to form a second bimetallic laminated plate. The annealing includes: performing annealing on the second bimetallic laminated plate.

Claims

1. A rolling method using corrugated rolls, comprising billet preparation, first-pass rolling, second-pass rolling, and annealing, wherein the billet preparation includes: stacking a cladding plate on a base plate to obtain a bimetallic laminated plate blank; the first-pass rolling includes: feeding the bimetallic laminated plate blank between two spaced-apart corrugated rolls for rolling to form a first bimetallic laminated plate, such that a grid-like wavy surface is formed on each of an upper surface and a lower surface of the first bimetallic laminated plate and at a bonding interface between the cladding plate and the base plate, wherein each of the corrugated rolls has a corrugated structure formed by selecting a closed shape as a cross-section and sweeping the cross-section along a plurality of left-handed helical lines and a plurality of right-handed helical lines as guide lines on a surface of the corrugated roll, the plurality of left-handed helical lines and the plurality of right-handed helical lines being interwoven; the second-pass rolling includes: feeding the first bimetallic laminated plate between two spaced-apart flat rolls for rolling to form a second bimetallic laminated plate, such that a flat surface is formed on each of an upper surface and a lower surface of the second bimetallic laminated plate, and the grid-like wavy surface is formed at the bonding interface; and the annealing includes: performing annealing on the second bimetallic laminated plate.

2. The method of claim 1, wherein each of the plurality of left-handed helical lines and the plurality of right-handed helical lines is a cylindrical helical line, and parametric equations of the plurality of left-handed helical lines are defined as follows: ${\begin{matrix} x = R \cos_{1} \\ y = R \sin_{1} \\ z = \frac{P}{2}_{1} = \frac{b}{T}_{1} = \frac{R}{\tan_{1}}_{1} \\ _{1} = t \\ P = {bn}_{1} \end{matrix}$ wherein R denotes a radius of the roll surface on which the cylindrical helical line is located, P denotes a lead of the cylindrical helical line, b denotes a pitch of the cylindrical helical line, T denotes a period of the cylindrical helical line, n.sub.1 denotes a count of starts of the plurality of right-handed helical lines, .sub.1 denotes a helical angle between the right-handed helical lines and an axis of the corrugated roll, parametric equations of the plurality of left-handed helical lines are defined as follows: ${\begin{matrix} x = R \cos_{2} \\ y = R \sin_{2} \\ z = - \frac{P}{2}_{2} + P = - \frac{b}{T}_{2} + P = - \frac{R}{\tan_{2}}_{2} + P \\ _{2} = t \\ P = {bn}_{2} \end{matrix}$ wherein R denotes the radius of the roll surface on which the cylindrical helical line is located, P denotes the lead of the cylindrical helical line, b denotes the pitch of the cylindrical helical line, T denotes the period of the cylindrical helical line, n.sub.2 denotes a count of starts of the plurality of left-handed helical lines, .sub.2 denotes a helix angle between the plurality of left-handed helical lines and the axis of the corrugated roll, the plurality of left-handed helical lines and the plurality of right-handed helical lines are defined as follows: $_{1} =_{2},$ $_{1} =_{2} = \arctan (\frac{2 R}{P}) 45 .$

3. The method of claim 1, wherein a cross-sectional profile of the closed shape includes a zigzag profile or a wavy profile.

4. The method of claim 3, wherein an included angle formed by two sides of each unit tooth profile on the cross-sectional profile is greater than or equal to 60; and/or, a distance between a peak point and a valley point of the cross-sectional profile along a radial direction of the corrugated rolls ranges from 3 mm to 5 mm.

5. The method of claim 1, wherein in the first-pass rolling, a reduction rate of the corrugated rolls ranges from 20% to 70%; and/or, in the second-pass rolling, a reduction rate of the flat rolls ranges from 10% to 40%.

6. The method of claim 1, further comprising: heating the bimetallic laminated plate blank in a protective atmosphere furnace under a hot-rolling process, wherein a heating temperature ranges from 350 C. to 450 C. and a holding time ranges from 12 min to 18 min; and/or, before feeding the first bimetallic laminated plate between the two spaced-apart flat rolls for rolling, heating the first bimetallic laminated plate in the protective atmosphere heating furnace using the hot-rolling process, wherein the heating temperature ranges from 350 C. to 450 C. and the holding time ranges from 4 min to 8 min.

7. The method of claim 1, wherein the performing annealing on the second bimetallic laminated plate includes: annealing the second bimetallic laminated plate in a protective atmosphere heating furnace at an annealing temperature ranging from 280 C. to 350 C. for an annealing duration ranging from 25 min to 35 min.

8. The method of claim 1, wherein after annealing the second bimetallic laminated plate, the method further comprises finishing, the finishing includes: straightening and edge-trimming an annealed second bimetallic laminated plate to obtain a finished product.

9. A rolling system, configured to perform a rolling method using corrugated rolls, the system comprising two driving devices, a flat roll set, and a corrugated roll set, wherein the flat roll set includes two spaced-apart flat rolls, the corrugated roll set includes two spaced-apart corrugated rolls, the two driving devices are configured to drive rotation of the flat roll set and rotation of the corrugated roll set, respectively, the corrugated roll set is configured to roll a bimetallic laminated plate blank to form a first bimetallic laminated plate, and the flat roll set is configured to roll the first bimetallic laminated plate to form a second bimetallic laminated plate.

10. The rolling system of claim 9, wherein a thickness ratio of a base plate to a cladding plate is less than or equal to 3, and the two corrugated rolls have a same structural parameter; or, the thickness ratio of the base plate to the cladding plate is greater than 3, and the two corrugated rolls have different structural parameters.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The accompanying drawings described herein are provided to further illustrate the present disclosure, constituting a part thereof. The illustrative embodiments and their descriptions in the present disclosure are intended to explain the present disclosure and shall not be construed as unduly limiting its scope. In the drawings:

[0014] FIG. 1 is a flowchart illustrating an exemplary process of a rolling method using corrugated rolls according to some embodiments of the present disclosure;

[0015] FIG. 2 is a schematic diagram illustrating an exemplary structure of a bimetallic laminated plate blank according to some embodiments of the present disclosure;

[0016] FIG. 3 is a schematic diagram illustrating first-pass rolling according to some embodiments of the present disclosure;

[0017] FIG. 4 is a schematic diagram illustrating an exemplary structure of a first bimetallic laminated plate according to some embodiments of the present disclosure;

[0018] FIG. 5 is a schematic diagram illustrating second-pass rolling according to some embodiments of the present disclosure;

[0019] FIG. 6 is a schematic diagram illustrating an exemplary structure of a second bimetallic laminated plate according to some embodiments of the present disclosure;

[0020] FIG. 7 is a schematic diagram illustrating an exemplary structure of a corrugated roll according to some embodiments of the present disclosure;

[0021] FIG. 8 is a radial cross-sectional view of the corrugated roll shown in FIG. 7;

[0022] FIG. 9 is a sectional view taken along line A-A of FIG. 7.

REFERENCE NUMERALS

[0023] 1bimetallic laminated plate blank; 11base plate; 12cladding plate; 13bonding interface; 2corrugated roll; 21left-handed helical line; 22right-handed helical line; 23cross-sectional profile; 3first bimetallic laminated plate; 31grid-like wavy surface; 4flat roll; 5second bimetallic laminated plate.

DETAILED DESCRIPTION

[0024] To make the technical problems addressed, the technical solutions, and the beneficial effects of the present disclosure clearer and more understandable, the present disclosure is further described in detail in conjunction with the accompanying drawings and embodiments below. It should be understood that the embodiments described herein are only for explaining the present disclosure, and are not intended to limit its scope.

[0025] Unless expressly stated otherwise, the term and/or as used herein denotes an inclusive relationship between the associated elements. For example, A and/or B means A alone, B alone, or both A and B together.

[0026] It should be noted that when an element is referred to as being fixed to or disposed on another element, it may be directly on the other element or indirectly on the other element. When an element is referred to as being connected to another element, it may be directly connected or indirectly connected to the other element.

[0027] Furthermore, the terms first and second are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined by first or second may explicitly or implicitly include one or more of such features. In the description of the present disclosure, a plurality of, the plurality of, and/or multiple, mean two or more, unless explicitly specified otherwise. The phrase a number of means one or more, unless explicitly specified otherwise.

[0028] In the description of the present disclosure, it should be understood that terms such as upper, lower, front, rear, left, and right indicate orientations or positional relationships based on those shown in the accompanying drawings. These terms are used only for ease of describing the present disclosure and simplifying the description, rather than indicating or implying that the referenced device or element must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the present disclosure.

[0029] In the description of the present disclosure, it should be noted that, unless otherwise expressly specified and defined, the terms mount, attach, and connect should be interpreted broadly. For example, a connection may be fixed, detachable, or integral; it may be mechanical or electrical; it may be direct or indirect via an intermediary; or it may refer to internal communication or their interaction between two elements. For those skilled in the art, the specific meanings of these terms in the present disclosure can be understood based on the context.

[0030] FIG. 1 is a flowchart illustrating an exemplary process of a rolling method using corrugated rolls according to some embodiments of the present disclosure. As shown in FIG. 1, process 100 includes the following operations:

[0031] S100, billet preparation: stacking a cladding plate on a base plate to obtain a bimetallic laminated plate blank.

[0032] The billet preparation refers to a process of making the bimetallic laminated plate blank.

[0033] The bimetallic laminated plate refers to a composite material formed by metallurgical bonding of two different metals. For example, the bimetallic laminated plate includes a titanium-steel laminated plate, a copper-steel laminated plate, or similar structures. A metallurgical bond refers to the bond formed by the mutual diffusion of atoms at the interface between two metals.

[0034] FIG. 2 is a schematic diagram illustrating an exemplary structure of a bimetallic laminated plate blank according to some embodiments of the present disclosure.

[0035] In some embodiments, as shown in FIG. 2, a bimetallic laminated plate blank 1 includes a base plate 11 and a cladding plate 12, with the cladding plate 12 being disposed on the base plate 11.

[0036] In some embodiments, the cladding plate 12 may be stacked and tightly pressed onto the base plate 11 to minimize a relative displacement between the cladding plate 12 and the base plate 11 during rolling.

[0037] The base plate refers to a plate located at a bottom layer in the bimetallic laminated plate. The cladding plate refers to a plate located at a surface layer in the bimetallic laminated plate.

[0038] In some embodiments, the base plate is made of a structural material to ensure essential properties of the bimetallic laminated plate. The cladding plate is made of a functional material to impart additional properties to the bimetallic laminated plate. For example, the base plate may be made of steel for ensuring toughness and strength of the bimetallic laminated plate. The cladding plate may be made of nickel, a nickel alloy, titanium, a titanium alloy, or similar materials, for improving corrosion resistance of the bimetallic laminated plate. The cladding plate may also be made of wear-resistant steel, martensitic stainless steel, etc., to improve abrasion resistance of the bimetallic laminated plate.

[0039] The materials used for the base plate and the cladding plate may include any other feasible combination of two metals.

[0040] In some embodiments of the present disclosure, by stacking the cladding plate and the base plate to form the bimetallic laminated plate blank, it ensures that the base plate and cladding plate do not experience misalignment or deviation when subjected to non-uniform tangential forces during rolling.

[0041] S200, first-pass rolling: feeding the bimetallic laminated plate blank between two spaced-apart corrugated rolls for rolling to form a first bimetallic laminated plate, such that a grid-like wavy surface is formed on each of an upper surface and a lower surface of the first bimetallic laminated plate and at a bonding interface between the cladding plate and the base plate, wherein each of the corrugated rolls has a corrugated structure formed by selecting a closed shape as a cross-section and sweeping the cross-section along a plurality of left-handed helical lines and a plurality of right-handed helical lines as guide lines on a surface of the corrugated rolls, the plurality of left-handed helical lines and the plurality of right-handed helical lines being interwoven.

[0042] The first-pass rolling refers to a process of rolling the bimetallic laminated plate blank.

[0043] FIG. 3 is a schematic diagram illustrating first-pass rolling according to some embodiments of the present disclosure.

[0044] In some embodiments, as shown in FIG. 3, the bimetallic laminated plate blank 1 is fed between two spaced-apart corrugated rolls 2 for rolling. The term spaced-apart means that the two corrugated rolls 2 do not contact each other.

[0045] A corrugated roll refers to a rotatable cylindrical component having a corrugated structure.

[0046] In some embodiments, the corrugated structure is formed by defining a closed shape as a cross-section and sweeping the cross-section along a plurality of left-handed helical lines 21 and a plurality of right-handed helical lines 22 as guide lines on a roll surface of the corrugated roll 2, the plurality of left-handed helical lines 21 and the plurality of right-handed helical lines 22 being interwoven. More descriptions regarding the corrugated structure may be found elsewhere in the present disclosure, e.g., the related descriptions in FIG. 7.

[0047] FIG. 4 is a schematic diagram illustrating an exemplary structure of a first bimetallic laminated plate according to some embodiments of the present disclosure.

[0048] In some embodiments, in the first-pass rolling, the bimetallic laminated plate blank 1 is plastically deformed under a pressure exerted by the two corrugated rolls 2 to form a first bimetallic laminated plate 3.

[0049] The first bimetallic laminated plate refers to a bimetallic laminated plate that is obtained after the first-pass rolling.

[0050] In some embodiments, as shown in FIG. 4, each of an upper surface and a lower surface of the first bimetallic laminated plate 3, and a bonding interface 13 between the cladding plate 12 and the base plate 11 is a grid-like wavy surface 31.

[0051] The bonding interface refers to an interface at which the cladding plate and the base plate undergo the metallurgical bonding, i.e., an interface at which the cladding plate and the base plate come into contact with each other.

[0052] In some embodiments of the present disclosure, the corrugated structure of the corrugated rolls induces strong plastic compression on the upper surface, the lower surface, and the bonding interface of the first bimetallic laminated plate, forming grid-like wavy surfaces, which alter a flow direction of the cladding plate and the base plate during rolling, thereby disrupting a deformation texture generated by rolling, mitigating the anisotropy in the upper and lower sections of the first bimetallic laminated plate, and enhancing the bonding strength of the bimetallic laminated plate.

[0053] S300, second-pass rolling: feeding the first bimetallic laminated plate between two spaced-apart flat rolls for rolling to form a second bimetallic laminated plate, such that a flat surface is formed on each of an upper surface and a lower surface of the second bimetallic laminated plate, and a grid-like wavy surface is formed at the bonding interface.

[0054] The second-pass rolling refers to a process of rolling the first bimetallic laminated plate.

[0055] A flat roll refers to a rotatable cylindrical component with a smooth surface.

[0056] FIG. 5 is a schematic diagram illustrating second-pass rolling according to some embodiments of the present disclosure. FIG. 6 is a schematic diagram illustrating an exemplary structure of a second bimetallic laminated plate according to some embodiments of the present disclosure.

[0057] In some embodiments, as shown in FIG. 5 and FIG. 6, in the second-pass rolling, the first bimetallic laminated plate 3 is plastically deformed under a pressure exerted by two flat rolls 4 to form a second bimetallic laminated plate 5.

[0058] The second bimetallic laminated plate refers to a bimetallic laminated plate that is obtained after the second-pass rolling.

[0059] In some embodiments, as shown in FIG. 6, each of the upper surface and the lower surface of the second bimetallic laminated plate 5 is a flat surface, and the bonding interface 13 is the grid-like wavy surface 31.

[0060] In some embodiments of the present disclosure, the first bimetallic laminated plate is rolled through the second-pass rolling using flat rolls. During the second-pass rolling, the grid-like wavy configurations of the upper surface and the lower surface of the first bimetallic laminated plate experience strong deformation, causing the upper surface and the lower surface of the first bimetallic laminated plate to be pressed into flat surfaces. Meanwhile, a compressive force exerted by the two flat rolls induces significant deformation in the metal near the bonding interface. Since the grid-like wavy surface is formed at the bonding interface, this configuration prevents warping and cracking during the rolling process, enhances the bonding strength between the two layers of the second bimetallic laminated plate, and improves the forming quality and material yield of the second bimetallic laminated plate.

[0061] S400, annealing: performing annealing on the second bimetallic laminated plate.

[0062] The annealing refers to a heat treatment process in which the second bimetallic laminated plate is slowly heated to a preset temperature, held for a sufficient duration, and then cooled at a predetermined rate. This process reduces hardness and residual stress while improving material properties.

[0063] In some embodiments of the present disclosure, by performing the annealing on the second bimetallic laminated plate completed after rolling, grains of the second bimetallic laminated plate are refined, and a microstructure of the second bimetallic laminated plate can be improved, thereby enhancing the plasticity and toughness of the second bimetallic laminated plate.

[0064] In some embodiments, before S100, the method further includes: Polishing to-be-bonded surfaces of the cladding plate 12 and base plate 11, respectively. The polishing removes oxide layers and oil stains from the surfaces of the cladding plate 12 and base plate 11, thereby improving the bonding strength after stacking and compression, and ensuring the forming quality and material yield of the second bimetallic laminated plate 5.

[0065] The to-be-bonded surfaces refer to surfaces where the cladding plate and the base plate are in contact, i.e., an upper surface of the base plate 11 and a lower surface of the cladding plate 12 in FIG. 2.

[0066] In some embodiments, the base plate 11 and the cladding plate 12 may be edge-fastened using riveting for convenient installation and disassembly. Alternatively, bonding, strapping, or other conventional fastening manners may be used between the base plate 11 and cladding plate 12.

[0067] FIG. 7 is a schematic diagram illustrating an exemplary structure of a corrugated roll according to some embodiments of the present disclosure.

[0068] In some embodiments, as shown in FIG. 3 and FIG. 7, each of the plurality of left-handed helical lines 21 and the plurality of right-handed helical lines 22 is a cylindrical helical line.

[0069] In some embodiments, taking a center point O of a base surface of the corrugated roll bearing the right-handed helical lines as an origin, the base surface containing with origin O defining the xOy plane, and a direction from the origin O pointing to a center of the opposite base surface as a z-axis direction, spatial Cartesian coordinate system Oxyz is established. Parametric equations of the right-handed helical lines 22 in the Oxyz coordinate system include:

[00001] ${\begin{matrix} x = R \cos_{1} \\ y = R \sin_{1} \\ z = \frac{P}{2}_{1} = \frac{b}{T}_{1} = \frac{R}{\tan_{1}}_{1} \\ _{1} = t \\ P = {bn}_{1} \end{matrix}$

wherein, R denotes a radius of the roll surface on which a cylindrical helical line is located, P denotes a lead of the cylindrical helical line, b denotes a pitch of the cylindrical helical line, T denotes a period of the cylindrical helical line, n.sub.1 denotes a count of starts of the plurality of right-handed helical lines, 1 denotes a helical angle between the right-handed helical lines and an axis of the corrugated roll, .sub.1 denotes an angular parameter of right-handed helical lines, denotes an angular velocity of the corrugated roll's rotation, t denotes a rotation time of the corrugated roll, and (x,y,z) denote coordinates of points on the right-handed helical lines 22 in the Oxyz coordinate system.

[0070] Parametric equations of the plurality of left-handed helical lines 21 in the Oxyz coordinate system include:

[00002] ${\begin{matrix} x = R \cos_{2} \\ y = R \sin_{2} \\ z = - \frac{P}{2}_{2} + P = - \frac{b}{T}_{2} + P = - \frac{R}{\tan_{2}}_{2} + P \\ _{2} = t \\ P = {bn}_{2} \end{matrix}$

wherein, R denotes the radius of the roll surface on which the cylindrical helical line is located, P denotes the lead of the cylindrical helical line, b denotes the pitch of the cylindrical helical line, T denotes the period of the cylindrical helical line, n.sub.2 denotes a count of starts of the plurality of left-handed helical lines, 2 denotes a helix angle between the plurality of left-handed helical lines and the axis of the corrugated roll, .sub.2 denotes an angular parameter of left-handed helical lines, denotes an angular velocity of the corrugated roll's rotation, t denotes the rotation time of the corrugated roll, and (x, y, z) denote coordinates of points on the left-handed helical lines 21 in the Oxyz coordinate system.

[0071] The left-handed helical lines 21 and the right-handed helical lines 22 satisfy the following conditions:

[00003] $_{1} =_{2},$ $_{1} =_{2} = \arctan (\frac{2 R}{P}) 45 .$

[0072] In some embodiments, .sub.1 and .sub.2 may be unequal, .sub.1 and .sub.2 may be unequal and less than 45, as long as production requirements are met.

[0073] It should be noted that the plurality of left-handed helical lines 21 and the right-handed helical lines 22 in the present disclosure are partial curves of cylindrical helical lines on the roll surface. Therefore the radius R of the roll surface on which the cylindrical helical line is located, the lead P of the cylindrical helical line, the pitch b of the cylindrical helical line, the period T of the cylindrical helical line, the count n.sub.1 of starts of the plurality of right-handed helical lines 22, the count n.sub.2 of starts of the plurality of left-handed helical lines 21, the helical angle .sub.1 and the helical angle .sub.2 are not labeled in the drawings.

[0074] As shown in FIG. 1, after determining the counts of starts, the pitch b, the lead P, the helical angle, etc., of the plurality of left-handed helical lines 21 and the plurality of right-handed helical lines 22 by the parametric equations above, an operator may select a closed shape as a cross-section and sweep the cross-section along one of the left-handed helical lines as a guide line on the roll surface. After completing multiple sweeps along n.sub.2 left-handed helical lines 21, the operator then sweeps the cross-section along one of the right-handed helical lines as a guide line on the roll surface, and completes multiple sweeps along n.sub.1 right-handed helical lines 22 to form the corrugated structure. A plurality of unit protrusions are formed on a surface of the corrugated structure at intersections of the left-handed helical lines 21 and the right-handed helical lines 22, and the plurality of unit protrusions are arrayed sequentially along the left-handed helical lines 21 and the right-handed helical lines 22. The unit protrusions generate oblique cross-flows on a surface of the bimetallic laminated plate 1, which promote transverse and oblique metal flow, disrupt specific rolling grain orientations in the bimetallic laminated plate 1, weaken rolling textures, reduce mechanical property anisotropy, and enhance the bonding strength between the cladding plate 12 and base plate 11 during rolling of the bimetallic laminated plate 1.

[0075] FIG. 8 is a radial cross-sectional view of the corrugated roll shown in FIG. 7. FIG. 9 is a sectional view taken along line A-A of FIG. 7.

[0076] In some embodiments, as shown in FIG. 8 and FIG. 9, a cross-sectional profile 23 of the closed shape includes a zigzag profile or a wavy profile, i.e., the cross-sectional profile 23 of the selected cross-section during sweeping may be the zigzag profile or the wavy profile. When the cross-sectional profile 23 is the zigzag profile, the closed shape of the selected cross-section is triangular. When the cross-sectional profile 23 is the wavy profile, the closed shape of the selected cross-section may be hemispherical, ellipsoidal, or other shapes with a smooth surface contour, which are not specifically limited herein. A contour trajectory of the wavy profile may be formed by sinusoidal curves, cosine curves, or spliced parabolic curves, as long as transitional corners on the surface of the corrugated structure are relatively smooth to reduce stress concentration at corner gaps during rolling and minimizes risks of warping and edge cracking in the rolled bimetallic laminated plate.

[0077] In some embodiments, as shown in FIG. 9, an included angle formed by two sides of each unit tooth profile on the cross-sectional profile 23 is greater than or equal to 60. For example, the included angle may be 60, 80, 95, 130, etc. There is no specific limitation on the included angle herein, as long as it is ensured that the corner gaps on the surface of the corrugated structure have smooth transitions, so as to mitigate stress concentration during rolling and to prevent warping or edge cracking in the bimetallic laminated plate.

[0078] In some embodiments, as shown in FIG. 8, a distance h between a peak point and a valley point of the cross-sectional profile 23 along a radial direction of each of the corrugated rolls 2 ranges from 3 mm to 5 mm. For example, the distance h may be 3 mm, 3.5 mm, 4 mm, 5 mm, etc. There is no specific limitation on the distance h herein, as long as smooth transitions at peak points and valley points on the surface of the corrugated structure are ensured, thereby avoiding stress concentration during rolling and to reduce risks of warping and edge cracking in the bimetallic laminated plate. The peak point and the valley point refer to a highest point and a lowest point of the cross-sectional profile 23 along the radial direction of the corrugated roll 2, respectively.

[0079] In some embodiments, in the first-pass rolling, a reduction rate of the corrugated rolls ranges from 20% to 70%; and/or, in the second-pass rolling, a reduction rate of the flat rolls ranges from 10% to 40%. For example, the reduction rate of the two corrugated rolls 2 may be 20%, 45%, 50%, 70%, etc., and the reduction rate of the flat rolls 4 may be 10%, 15%, 30%, 40%, etc. There is no specific limitation on the reduction rate of the two corrugated rolls 2 and the reduction rate of the two flat rolls 4 herein, as long as it is ensured that the second bimetallic laminated plate 5 formed by rolling has a good bonding strength.

[0080] The reduction rate refers to a ratio of compression of a material thickness before and after rolling. For example, if a thickness of the bimetallic laminated plate blank is 10 cm before the first-pass rolling and a thickness of the first bimetallic laminated plate obtained after the first-pass rolling is 8 cm, the reduction rate of the corrugated rolls 2 in the first-pass rolling is 20%.

[0081] In some embodiments, the reduction rate may be adjusted by adjusting a roll spacing of the corrugated rolls 2 or a roll spacing of the flat rolls 4, and a magnitude of the reduction rate is determined based on a metal material type, a rolling wave amplitude, or the like. If the reduction rate is too large, it may cause the bimetallic laminated plate blank 1 to crack. If the reduction rate is too small, it may prevent the formation of the grid-like wavy surface 31 at the bonding interface 13 between the base plate 11 and the cladding plate 12, resulting in a poor bonding strength of the bimetallic laminated plate blank 1. At the same time, the roll spacing of the corrugated rolls 2, the roll spacing of the flat rolls 4, and the wave amplitude A of the corrugated rolls 2, etc., may be adaptively adjusted based on the reduction rate, the material of the bimetallic laminated plate blank 1, or the like, as long as it is ensured that the grid-like wavy surface 31 is formed at the bonding interface 13 of the first bimetallic laminated plate 3 or the second bimetallic laminated plate 5.

[0082] In some embodiments, the rolling method using corrugated rolls further includes: before feeding the bimetallic laminated plate blank between the two spaced-apart corrugated rolls for rolling, heating the bimetallic laminated plate blank 1 in a protective atmosphere heating furnace using a hot-rolling process, wherein a heating temperature ranges from 350 C. to 450 C. and a holding time ranges from 12 min to 18 min. For example, the heating temperature may be 350 C., 360 C., 400 C., 415 C., 430 C., 450 C., etc., and the holding time may be 12 min, 13 min, 15 min, 16 min, 18 min, etc. The heating temperature and the holding time are not specifically limited, as long as requirements for rolling the bimetallic laminated plate 1 are satisfied. Preferably, the heating temperature is 400 C. and the holding time is 15 min when using the corrugated rolls 2 for rolling.

[0083] The hot-rolling process refers to a rolling process performed above a recrystallization temperature of metals. By heating the metal above its recrystallization temperature and maintaining the temperature, new crystal nuclei may form within the metal structure, thereby improving the processability of the metal.

[0084] The protective atmosphere heating furnace refers to a device that heats metals by introducing gases during heating and holding processes to prevent metal oxidation. The input gases include nitrogen, argon, ammonia, or the like, or any combination thereof.

[0085] In some embodiments of the present disclosure, the hot-rolling process enhances metal plasticity and reduces deformation resistance, improves the transfer of the corrugated structure of the corrugated rolls 2 to the bonding interface 13 to form the grid-like wavy surface 31, and increases rolling process efficiency.

[0086] In some embodiments, before feeding the first bimetallic laminated plate 3 between the two spaced-apart flat rolls 4 for rolling, the rolling method using corrugated rolls further includes: heating the first bimetallic laminated plate 3 in the protective atmosphere heating furnace using the hot-rolling process, wherein the heating temperature ranges from 350 C. to 450 C. and the holding time ranges from 4 min to 8 min. For example, the heating temperature may be 350 C., 360 C., 400 C., 415 C., 430 C., 450 C., etc. The holding time may be 4 min, 5 min, 6 min, 7.5 min, 8 min, etc. The heating temperature and the holding time are not specifically limited, as long as requirements for rolling the first bimetallic laminated plate 3 are satisfied. Preferably, the heating temperature is 400 C. and the holding time is 5 min when using the flat rolls 4 for rolling.

[0087] In some embodiments of the present disclosure, the holding time in the hot-rolling process before the second-pass rolling is shorter than the holding time in the hot-rolling process before the first-pass rolling, so that the upper surface and the lower surface of the first bimetallic laminated plate 3 have higher plasticity and lower deformation resistance, and plasticity and deformation resistance at the bonding interface 13 undergo minimal changes. Consequently, during rolling by the flat rolls 4, the upper surface and the lower surface of the first bimetallic laminated plate 3 can be more easily flattened, reducing the impact on the structural rolling deformation of the grid-like wavy surface 31 formed at the bonding interface 13, thereby improving the bonding strength of the second bimetallic laminated plate 5 obtained from rolling.

[0088] In some embodiments, in operations S200 and S300, cold-rolling may be used. No specific limitations are imposed on the rolling processes for the first-pass rolling and the second-pass rolling, as long as the grid-like wavy surface 31 can be formed at the bonding interface 13.

[0089] The cold-rolling refers to the rolling of metals at room temperature.

[0090] In some embodiments, performing the annealing on the second bimetallic laminated plate includes: annealing the second bimetallic laminated plate in the protective atmosphere heating furnace at an annealing temperature ranging from 280 C. to 350 C. for an annealing duration ranging from 25 min to 35 min. For example, the annealing temperature may be 280 C., 295 C., 300 C., 320 C., 335 C., 350 C., etc., and the annealing duration may be 25 min, 26 min, 28 min, 30 min, 35 min, etc. No specific limitations are imposed on the annealing temperature and the annealing duration herein, provided that the residual stress of the second bimetallic laminated plate 5 after rolling can be reduced.

[0091] In some embodiments of the present disclosure, by annealing the second bimetallic laminated plate 5 in the protective atmosphere heating furnace improves the structural properties of the second bimetallic laminated plate 5, refining the inner and outer grain layers of the second bimetallic laminated plate 5 are simultaneously refined, thereby ensuring the forming quality and material yield of the second bimetallic laminated plate 5.

[0092] In some embodiments, after annealing the second bimetallic laminated plate 5 in S400, the rolling method using corrugated rolls further includes finishing.

[0093] The finishing refers to a series of processing operations carried out to make an annealed second bimetallic laminated plate have a size, a shape, and properties required by technical conditions. For example, the finishing includes straightening and edge-trimming the annealed second bimetallic laminated plate to obtain a finished product, or the like.

[0094] In some embodiments, the operator may perform detailed trimming and processing on the second bimetallic laminated plate 5 to remove surface defects such as burrs and oxide scales, improve surface finish and hardness, and conduct dimensional inspection and correction to produce the final product, thereby extending the service life of the second bimetallic laminated plate 5 and improving the forming quality of the second bimetallic laminated plate 5.

[0095] Effects of the rolling method using corrugated rolls described in the present disclosure are described below with reference to Table 1.

TABLE-US-00001 TABLE 1 Comparison of different parameters of second bimetallic laminated plates 5 obtained by two existing rolling methods for and the method in the present disclosure Second bimetallic Second bimetallic Second bimetallic laminated plate 5 laminated plate 5 laminated plate 5 obtained by the obtained by a obtained by a method in the manner in manner in present Comparative Comparative Parameter disclosure Example 1 Example 2 Plate warping Not observed Severe Noticeable Edge cracking Not observed Severe Slight Lap shear 42.57mpa 36.31mpa 37.96mpa strength (rolling direction) Lap shear 40.99mpa 29.42mpa 35.73mpa strength (transverse direction) Tensile strength 279.65 N/mm 236.11 N/mm 259.30 N/mm (rolling direction) Elongation 12.33% 6.72% 8.99% (rolling direction) Tensile strength 275.48 N/mm 228.64 N/mm 262.14 N/mm (transverse direction) Elongation 11.86% 6.30% 9.01% (transverse direction) Erichsen value 6.32 5.02 5.78

[0096] It should be noted that the three rolling methods in the above table used 5052 grade aluminum alloy as the base plate 11 and AZ31 grade magnesium alloy plate as the cladding plate 12. The base plate 11 and the cladding plate 12 have a length of 100 mm, a width of 80 mm, and a height of 2 mm, and the thickness ratio of the base plate 11 to the cladding plate 12 is 1 when rolling. The corrugated rolls 2 used in the first-pass rolling of the rolling method using corrugated rolls of the present disclosure are shown in FIG. 3 and FIG. 7. Comparative Example 1 used flat rolls 4 for the first-pass rolling and the second-pass rolling, and Comparative Example 2 used corrugated rolls with a surface structure formed by intersecting transverse and axial corrugations for the first-pass rolling and flat rolls 4 for the second-pass rolling. The mechanical property test data in the table were measured on an electronic universal testing machine, and the forming properties were measured on a testing machine using a controlled variable technique, with all other parameters being identical except for the rolling methods used during processing.

[0097] Table 1 shows, compared with the existing manners in Comparative Examples 1 and 2, the second bimetallic laminated plate 5 obtained by the method of the present disclosure enables the formation of the grid-like wavy surface 31 at the bonding interface 13 between the base plate 11 and cladding plate 12 in the obtained second bimetallic laminated plate 5. This effectively prevents damage to the bonding interface 13 formed in previous rolling passes during subsequent passes, improves the bonding strength between the base plate 11 and cladding plate 12, effectively suppresses warping and edge cracking of the second bimetallic laminated plate 5, refines the grain structure of the second bimetallic laminated plate 5, and significantly enhances the mechanical properties and secondary forming performance.

[0098] Some embodiments of the present disclosure further provide a rolling system, the system being configured to perform the rolling method using corrugated rolls described above. The system includes two driving devices, a flat roll set, and a corrugated roll set. The flat roll set comprises two spaced-apart flat rolls 4, the corrugated roll set comprises two spaced-apart corrugated rolls 2, and the two driving devices are configured to drive rotation of the flat roll set and rotation of the corrugated roll set, respectively. The corrugated roll set is configured to roll the bimetallic laminated plate blank 1 to form the first bimetallic laminated plate 3, and the flat roll set is configured to roll the first bimetallic laminated plate 3 to form the second bimetallic laminated plate 5.

[0099] More descriptions of the corrugated rolls 2 and the flat rolls 4 are provided in the related descriptions above.

[0100] In some embodiments, the operator first starts one of the two driving devices, causing a drive end of the driving device to drive the corrugated roll set, at which time the cladding plate 12 and the base plate 11 are stacked to obtain the bimetallic laminated plate blank 1, and the bimetallic laminated plate blank 1 is fed between two spaced-apart corrugated rolls 2 for the first-pass rolling. After the first-pass rolling is completed, due to the influence of the corrugated structure on the surface of the corrugated rolls 2, the resulting first bimetallic laminated plate 3 develops mutual interlocking between the cladding plate 12 and the base plate 11, forming grid-like wavy surfaces 31 on the upper surface and the lower surface of the first bimetallic laminated plate 3 as well as at the bonding interface 13. Subsequently, the another driving device is activated to operate the flat roll set, at which time the first bimetallic laminated plate 3 is positioned between spaced-apart flat rolls 4 for the second-pass rolling. The final second bimetallic laminated plate 5 retains the corrugated structure transferred from the roll surface of the corrugated roll 2, and the upper surface and the lower surface of the second bimetallic laminated plate 5 are flattened.

[0101] The rolling system in the present disclosure uses the corrugated rolls 2 to confine the plastic deformation of the cladding plate 12 and the base plate 11 within a specific region during rolling via the corrugated structure. The corrugated structure prevents severe edge cracking caused by strong tensile stresses along the rolling direction, thereby enhancing the bonding strength of the second bimetallic laminated plate 5 formed after the second-pass rolling.

[0102] In some embodiments, a thickness ratio of the base plate 11 to the cladding plate 12 is less than or equal to 3, and the two corrugated rolls 2 have the same structural parameter. Alternatively, the thickness ratio of the base plate 11 to the cladding plate 12 is greater than 3, and the two corrugated rolls 2 have different structural parameters. For example, the thickness ratio of the base plate 11 to the cladding plate 12 may be 1, 2, 3, 4, 5, 7, etc. The thickness ratio of the base plate 11 to the cladding plate 12 is not specifically limited herein. If the thickness ratio of the base plate 11 to the cladding plate 12 is less than or equal to 3, the two corrugated rolls 2 may be configured with the same structural parameter. If the thickness ratio of the base plate 11 to the cladding plate 12 is greater than 3, the two corrugated rolls 2 may be configured with different structural parameters to ensure the formation of the grid-like wavy surface 31 at the bonding interface 13 between the base plate 11 and the cladding plate 12, thereby improving the forming quality and material yield of the second bimetallic laminated plate 5.

[0103] The structural parameter refers to a parameter related to a physical structure of the corrugated rolls 2. For example, the structural parameter includes roll diameter and roll width, or the like of the corrugated rolls 2.

[0104] Some embodiments of the present disclosure provide a rolling method using corrugated rolls, including:

[0105] S100, billet preparation: stacking and pressing a cladding plate on a base plate to obtain a bimetallic laminated plate blank.

[0106] S200, first-pass rolling: feeding the bimetallic laminated plate blank between two spaced-apart corrugated rolls for rolling to form a first bimetallic laminated plate, such that a grid-like wavy surface is formed on each of an upper surface and a lower surface of the first bimetallic laminated plate and at a bonding interface between the cladding plate and the base plate, wherein each of the corrugated rolls has a corrugated structure formed by using a closed shape as a cross-section and sweeping the cross-section along a plurality of left-handed helical and a plurality of right-handed helical lines as guide lines on the surface of the corrugated rolls, the left-handed helical lines and right-handed helical lines being interwoven.

[0107] S300, second-pass rolling: feeding the first bimetallic laminated plate between two spaced-apart flat rolls for rolling to form a second bimetallic laminated plate, such that a flat surface is formed on each of an upper surface and a lower surface of the second bimetallic laminated plate, and the grid-like wavy surface is formed at the bonding interface.

[0108] S400, annealing: performing annealing on the second bimetallic laminated plate.

[0109] In some embodiments, the left-handed helical lines and the right-handed helical lines are cylindrical helical lines, and parametric equations of the right-handed helical lines include:

[00004] ${\begin{matrix} x = R \cos_{1} \\ y = R \sin_{1} \\ z = \frac{P}{2}_{1} = \frac{b}{T}_{1} = \frac{R}{\tan_{1}}_{1} \\ _{1} = t \\ P = {bn}_{1} \end{matrix}$

wherein R denotes a radius of the roll surface on which the cylindrical helical line is located, P denotes a lead of the cylindrical helical line, b denotes a pitch of the cylindrical helical line, T denotes a period of the cylindrical helical line, n.sub.1 denotes a count of starts of the plurality of right-handed helical lines, 1 denotes a helical angle between the right-handed helical lines and an axis of the corrugated roll.

[0110] Parametric equations of the left-handed helical lines include:

[00005] ${\begin{matrix} x = R \cos_{2} \\ y = R \sin_{2} \\ z = - \frac{P}{2}_{2} + P = - \frac{b}{T}_{2} + P = - \frac{R}{\tan_{2}}_{2} + P \\ _{2} = t \\ P = {bn}_{2} \end{matrix}$

wherein R denotes the radius of the roll surface on which the cylindrical helical line is located, P denotes the lead of the cylindrical helical line, b denotes the pitch of the cylindrical helical line, T denotes the period of the cylindrical helical line, n.sub.2 denotes a count of starts of the plurality of left-handed helical lines, 2 denotes a helix angle between the plurality of left-handed helical lines and the axis of the corrugated roll.

[0111] The left-handed helical lines and the right-handed helical lines satisfy the following conditions:

[00006] $_{1} =_{2},$ $_{1} =_{2} = \arctan (\frac{2 R}{P}) 45 .$

[0112] In some embodiments, a cross-sectional profile of the closed shape includes a zigzag profile or a wavy profile.

[0113] In some embodiments, an included angle formed by two sides of each unit tooth profile on the cross-sectional profile is greater than or equal to 60; and/or, a distance between a peak point and a valley point of the cross-sectional profile along a radial direction of the corrugated rolls ranges from 3 mm to 5 mm.

[0114] In some embodiments, in the first-pass rolling, a reduction rate of the corrugated rolls ranges from 20% to 70%; and/or, in the second-pass rolling, a reduction rate of the flat rolls ranges from 10% to 40%.

[0115] In some embodiments, the rolling method using corrugated rolls further includes: before feeding the bimetallic laminated plate blank between the two spaced-apart corrugated rolls, heating the bimetallic laminated plate blank in a protective atmosphere heating furnace using a hot-rolling process, wherein a heating temperature ranges from 350 C. to 450 C. and a holding time ranges from 12 min to 18 min; and/or, before feeding the first bimetallic laminated plate between the two spaced-apart flat rolls for rolling, the method further includes: heating the first bimetallic laminated plate in a protective atmosphere heating furnace using a hot-rolling process, wherein a heating temperature ranges from 350 C. to 450 C. and a holding time ranges from 4 min to 8 min.

[0116] In some embodiments, performing the annealing on the second bimetallic laminated plate includes: annealing the second bimetallic laminated plate in a protective atmosphere heating furnace at an annealing temperature ranging from 280 C. to 350 C. for an annealing duration ranging from 25 min to 35 min.

[0117] In some embodiments, after annealing the second bimetallic laminated plate, the method further includes:

[0118] S500, finishing: straightening and edge-trimming an annealed second bimetallic laminated plate to obtain a finished product.

[0119] Some embodiments of the present disclosure provide a rolling system. The system is configured to perform the rolling method using corrugated rolls as described in one or more of the preceding embodiments. The system comprises two driving devices, a flat roll set, and a corrugated roll set. The flat roll set includes two spaced-apart flat rolls, and the corrugated roll set includes two spaced-apart corrugated rolls. The two driving devices are configured to drive rotation of the flat roll set and rotation of the corrugated roll set, respectively. The corrugated roll set is configured to roll a bimetallic laminated plate blank to form a first bimetallic laminated plate. The flat roll set is configured to roll the first bimetallic laminated plate to form a second bimetallic laminated plate.

[0120] In some embodiments, a thickness ratio of a base plate to a cladding plate is less than or equal to 3, and two corrugated rolls have a same structural parameter; or, the thickness ratio of the base plate to the cladding plate is greater than 3, and the two corrugated rolls have different structural parameters.

[0121] Having thus described the basic concepts, it may be apparent to those skilled in the art after reading this detailed disclosure that the foregoing detailed disclosure is intended to be presented by way of example only and is not limiting. Various alterations, improvements, and modifications may occur and are intended to those skilled in the art, though not expressly stated. These alterations, improvements, and modifications are intended to be suggested by this disclosure and are within the spirit and scope of the exemplary embodiments of this disclosure.

[0122] Moreover, certain terminology has been used to describe embodiments of the present disclosure. For example, the terms one embodiment, an embodiment, and/or some embodiments mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. Therefore, it is emphasized and should be appreciated that two or more references to an embodiment, one embodiment, or an alternative embodiment in various portions of the present disclosure do not necessarily refer to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined as suitable in one or more embodiments of the present disclosure.

[0123] Furthermore, the order of processing elements or sequences, or the use of numbers, letters, or other designations, is not intended to limit the claimed processes and methods to any order except as may be specified in the claims. Although the above disclosure discusses various embodiments through examples of the disclosure, it should be understood that such detail is solely for that purpose and that the appended claims are not limited to these embodiments, but, on the contrary, are intended to cover modifications and equivalent arrangements that are within the spirit and scope of the disclosed embodiments. For example, although the implementation of various components described above may be embodied in a hardware device, it may also be implemented as a software-only solution, e.g., installation on an existing server or mobile device.

[0124] Similarly, it should be appreciated that in the foregoing description of embodiments of the present disclosure, various features are sometimes grouped together in a single embodiment, figure, or description thereof to streamline the disclosure aiding in the understanding of one or more of the various inventive embodiments. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed object matter requires more features than are expressly recited in each claim. Rather, inventive embodiments lie in less than all features of a single foregoing disclosed embodiment.

[0125] In some embodiments, the numbers expressing quantities, properties, and so forth used to describe and claim certain embodiments of the application are modified in some instances by the term about, approximate, or substantially. For example, about, approximate or substantially may indicate 20% variation of the value it describes, unless otherwise stated. Accordingly, in some embodiments, the numerical parameters set forth in the written description and attached claims are approximations that may vary depending upon the desired properties sought by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the application are approximations, the numerical values set forth in the specific examples are reported as precisely as possible.

[0126] Each of the patents, patent applications, publications of patent applications, and other material, such as articles, books, specifications, publications, documents, things, and/or the like, referenced herein is hereby incorporated herein by this reference in its entirety for all purposes, excepting any prosecution file history associated with same, any of same that is inconsistent with or in conflict with the present document, or any of same that may have a limiting effect as to the broadest scope of the claims now or later associated with the present document. By way of example, should there be any inconsistency or conflict between the description, definition, and/or the use of a term associated with any of the incorporated material and that associated with the present document, the description, definition, and/or the use of the term in the present document shall prevail.

[0127] In closing, it is to be understood that the embodiments of the application disclosed herein are illustrative of the principles of the embodiments of the application. Other modifications that may be employed may be within the scope of the embodiments of the application. Thus, by way of example, but not of limitation, alternative configurations of the embodiments of the application may be utilized in accordance with the teachings herein. Accordingly, embodiments of the present application are not limited to that precisely as shown and described.

ROLLING METHODS USING CORRUGATED ROLLS AND ROLLING SYSTEMS

Assignee

Inventors

Cpc classification

Classification Explorer

B21B2267/12

PERFORMING OPERATIONS; TRANSPORTING

Classification Explorer

B21B1/227

PERFORMING OPERATIONS; TRANSPORTING

Classification Explorer

B21B3/00

PERFORMING OPERATIONS; TRANSPORTING

Classification Explorer

B21B2001/225

PERFORMING OPERATIONS; TRANSPORTING

Classification Explorer

B21B2267/10

PERFORMING OPERATIONS; TRANSPORTING

Classification Explorer

B21B15/00

PERFORMING OPERATIONS; TRANSPORTING

International classification

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B21B1/22

PERFORMING OPERATIONS; TRANSPORTING

Classification Explorer

B21B15/00

PERFORMING OPERATIONS; TRANSPORTING

Classification Explorer

B21B3/00

PERFORMING OPERATIONS; TRANSPORTING

Abstract

Claims

Description